There are different designs for the brake assembly for bicycles and generally includes the clamp type and the disk brake type, wherein the clamp type clamps the wheel rim to stop the wheel and the disk brake type includes a disk connected to the hub and the wheel is stopped by stopping the disk.
For the clamp type brake assembly, there are cantilever type, C-type, V-type, and hydraulic type, wherein the cantilever type includes two cantilevers locate don two sides of the wheel rim and a brake cable is cooperated with a straddle cable to form an inverted V-shaped arrangement so that when the straddle cable is pulled upward by the brake cable, the two cantilevers are pivoted so as to move the two respective brake pads to contact the wheel rim. C-type includes a brake cable located on one side of the brake assembly and is connected with one of the two arms. The arms are pivoted to stop the wheel by pulling the brake cable.
The C-type brake assembly is used for those bicycles using narrow tire and one of the C-type brake assemblies is disclosed in U.S. Pat. No. 7,000,739 and includes two arms pivotably connected to a bolt and a cam lever and a quick release latch are cooperated with the brake assembly. Another C-type brake assembly is disclosed in U.S. Pat. No. 7,422,090 and includes a link unit which is located between the first and second arms so as to activate the two arms to stop the wheel.
However, the distance between the pivot point of the link unit and the force applying point of the U.S. Pat. No. 7,422,090 is too short so that it requires a significant force to operate the brake assembly. The force has to overcome the resistance from the link unit and the spring member, so that the brake assembly has lower sensitivity which increases the response time to slower or stop the bicycle.
The present invention intends to provide a brake assembly that includes a link unit whose links have optimal arrangement such that the brake action can be made with less force within short response time.